The prevalence of atrial fibrillation (AF) and its related mortality have been holding fairly steady in Europe overall during the past 3 decades, but a more discriminating data dive shows they vary widely among individual European nations and indicates what may seem like a paradox, researchers say. The arrhythmia has become more common and more deadly over the years in some countries but not others, and those where AF-related mortality is climbing fastest are among the continent's most affluent.
The findings clash with perceptions of a worsening AF epidemic internationally as the industrialized world's elder population grows and that health outcomes are better in countries with more robust economies, the group proposes.
Also in their analysis, based on 28 years of numbers from 20 European Union members as documented in the 2017 Global Burden of Disease Database, AF prevalence and related mortality were consistently higher for women than for men, and their per-case mortality rose faster. That mortality gap between the sexes, it shows, widened at a faster pace in some countries than in others.
There was an overall pattern of constant AF incidence rates and AF-related mortality across Europe from 1990 through 2017, but with broad heterogeneity by country, Becker M. Al-Khayatt, MBBS, told theheart.org | Medscape Cardiology. "Each country has its own trends that would benefit from a national investigation of AF burden levels."
Al-Khayatt, from Croydon University Hospitals NHS Trust, London, and the international Medical Data Research Collaborative, is lead author on the January 25 publication of the analysis in the European Heart Journal.
Variable Variation by Country
"Austria, Denmark, and Sweden have incidences peaking in the middle of the study period which then decline toward the end," the group's report states as examples of such trends. "Italy has a sharp rise in incidence in the late 1990s, and in Portugal there is a period of rapid decline in AF incidence between 2006 and 2009."
Mortality related to AF rose faster than AF incidence in countries with the highest gross domestic products (GDP), especially Sweden, Denmark, and Germany, the group reports. Despite those nations' relative affluence, notes the report, their AF incidence and mortality significantly exceeded countries with the lowest GDPs, including a number of Eastern European countries and Baltic states.
"Mortality attributable to AF per case," it contends, "has not improved over time and in many nations is actually increasing, despite apparent advances in AF care."
That's surprising, Al-Khayatt said. "There's almost a failure to improve the situation even with all the various additions to our treatment arsenal," including better understanding of rhythm control and rate control therapies, the advent of catheter ablation, strides in oral anticoagulation, and improved services for following patients clinically.
The observed patterns don't apply to individuals, nor should they be extrapolated to other world regions, he cautioned. Within each country, the patterns would break down at the individual level and so shouldn't be interpreted as "being affluent puts you at increased risk," Al-Khayatt said. And "Europe in general is quite affluent. Even the country with the lowest median GDP was still above average compared to the rest of the world."
Other countries covered by the analysis were Belgium, Bulgaria, Croatia, Czech Republic, Finland, France, Greece, Hungary, Ireland, Italy, the Netherlands, Poland, Portugal, Romania, Spain, and the United Kingdom.
As to explanations for the curious findings, the authors could only speculate. "A survivor effect is one possibility, with patients surviving long enough to suffer AF and its adverse consequences in higher-GDP countries," they write.
Differences in screening capability may be involved, Al-Khayatt proposed. For example, there may be variation in whether a country's healthcare system can afford to include electrocardiography at routine clinic visits, "or just more guidance for healthcare staff in looking for atrial fib." And, he added, "there are probably some underlying cultural differences that might explain it, as well as the actual intrinsic differences in how healthcare works in each country."
Variation in Sex Disparities
In all countries, the estimated AF case-fatality rate was higher for women than for men. Germany had the greatest increase in disparity between women and men over the study period; the case fatality rate was 43.6% higher for women than men in 1990 and 74.5% higher in 2017. At the other extreme, the case fatality rate for women in Bulgaria was only 5.4% higher than the men's rate.
"There are probably multiple reasons for the disparities," Al-Khayatt said. Perhaps there are biologic or pathophysiologic differences between women and men, such as in AF-related thromboembolic risk. "Or it might be that women present a bit later and are treated less aggressively when AF does occur," he said. "There might be some kind of intrinsic bias in terms of treating women versus men. Obviously, this is something that's worth looking into."
Al-Khayatt and coauthors had no disclosures.
Eur Heart J. Published online January 25, 2021. Full text
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Cite this: Curious Variation in Atrial Fib Incidence, Mortality Across Europe - Medscape - Jan 29, 2021.